Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
KJV

2 Chronicles 21:12

And there came a writing to him from Elijah the prophet, saying, Thus saith the Lord God of David thy father, Because thou hast not walked in the ways of Jehoshaphat thy father, nor in the ways of Asa king of Judah,

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